Over-heating

[Sue]

Hi - brand new to forum and thankful that it exists! I have an 02' Ranger 4.0 that had little to no heat, and coolant leak at water inlet housing. I replaced housing assembly (housing,t-stat, temp & gauge sensors), and burped system til heat came through. This was a few months ago. Suddenly 2 days ago, coolant leak at or near water inlet housing, loud gurgle from heater core, and no heat. Besides pinpointing source of leak, any thoughts on how to start finding the issue? Thank you for any advice!

 

[DILLARD000]

...02' Ranger 4.0 that had little to no heat, and coolant leak at water inlet housing
...replaced housing assembly (housing,t-stat, temp & gauge sensors), and burped system...a few months ago.
...2 days ago, coolant leak at or near water inlet housing, loud gurgle from heater core, and no heat

Welcome to the herd!
Did you replace original black plastic ThermoStat Housing with another plastic housing?
If so, the plastic TStatHousing was a bad design originally, & replacement plastic housings (ford or otherwise) are still junk.

Do you have a coolant leak, into the "cave" behind the TStatHousing under the IntakeManifold,
or a leak onto the ground down the front back of the engine around the tranny bellhousing,
or a leak down the front of the engine over the CoolantPump?
Any of these leaks is likely coming from the notorious factory TStatHousing (original or replacement plastic junk).

Hopefully you did not run the coolant system dry, overheat & damage the engine?
If you still have a workable engine, then best to replace the junk plastic TStatHousing with an aluminum version.
If your 2002 truck has never had the TStatValve\CoolantPump\Radiator+Cap\AllCoolantHoses\HeaterControlValve\Fan+Clutch...
changed, time to seriously consider doing so. Details of my adventures doing this at

Engine Coolant ThermoStat

In early 2019 & 19+ years, the FactoryOE ThermoStat Housing on my 2001 Ford ExplorerSportTrac started to leak per the pics below; at first just an irritation, this leak steadily grew much worse. Under the Throttle on the V6~4.0L~SOHC engines TopFront in several 1997~2012 models, the FactoryOE...

2001fordexplorersporttrac.fandom.com

Engine Coolant HeaterValve

It seems that the engineered DesignLifeTime for this vehicle, assembled in 2000, was\is around 18 years; starting in 2019, during every Coolant system maintenance task (ThermoStat Valve, Hoses, Flush+Fill,...), yet more OEM plastic parts (TStatHousing, HoseTeeFitting, RadiatorTank...)...

2001fordexplorersporttrac.fandom.com

Engine Coolant Fan+Clutch+Pump

Coolant Pump \ Penetrant Soak + SiliconLub Bearing BothSides Ford# 6L2z-8501-a \ f77z-8501-ad \ pw458 Coolant Pump FiberGasket With HiTemp RTVSealant LiteCoat BothSides Ford# fotz-8507-a \ FelPro# 35474 HiTemp RTVSealant 750f PermaTex# 27038.OptimumRed \ 700f PermaTex# 81878.UltraCopper Coolant...

2001fordexplorersporttrac.fandom.com

Engine Coolant Radiator+Cap

In 2020Jun, while replacing TimingTensioners, the ThermoStatHousing had to be removed for access to left Tensioner; while draining Coolant, discovered a 6" split & leak in the old 2RowPlasticTankedRadiators right tank & drain. Described here is the new 4RowAllAlumRadiator which I installed...

2001fordexplorersporttrac.fandom.com

Hopefully this helps.
D

 

[RonD]

Welcome to TRS

Water inlet housing?

The thermostat housing has the upper radiator hose attached, water flows out of that hose and into the radiator
Water comes back in from lower radiator hose into the water pump

There is also a heater hose attached to the thermostat housing, water flows out of that to the heater(by-pass valve), after water goes thru heater core it comes back into water pump

The thermostat housings on the 4.0l SOHC engine(2002 Ranger) are notorious for cracking and leaking, but usually not a new one

Best way to find a coolant leak, if you can't find/see it by inspection, is with a cooling system pressure tester, you can rent these
Its basically a solid fit radiator cap with a hand pump and a pressure gauge attached to it
When engine is COLD you remove cap, top up coolant/water
Install the pressure cap, and pump the pressure up to 20psi, system normally runs at 16psi
Then you watch pressure, it will start to drop if there is a leak
Then you start looking for the leak, with a cold engine is much much easier to see coolant dripping on the ground or pooling up somewhere

 

[Sue]

Thanks for the feedback Ron and D - yes, sadly, it's the same plastic housing. But it was such a good deal coming as an assembly with all the stuff I needed...I guess I was blinded by the price. I will go grab a psi test kit from my local parts store and will come back with results tomorrow. My resources are very limited since I stopped working full time to care of my mom, but thanks D for posting all your stories about the fun I have to look forward to in "Replacementville"...

 

[RonD]

Also when refilling a cooling system just remove the heater hose at the firewall that comes from thermostat housing(or near it)
That will let ALL the air out as the system fills up, once coolant starts to come out of that hose put it back on
Done deal, no air for sure
No jacking up the front, or parking uphill, lol, no burping


And while on the subject,.......swap heater hoses around at the firewall every 2 years, at least, but any time is a good time
Heater cores have no "direction" of coolant flow, no IN or OUT
But what happens over the years is bits of debris will come in and collect in passages in the core(same happens to radiators)
By reversing the flow thru the core you are Back Flushing this debris out the way it came in, while you drive
You can get twice or three times the life from a heater core this way, also better HEAT in the cab